1. Field of the Invention
The invention relates to an antenna frame for receiving and fixing an antenna, an antenna structure having the antenna frame, and a watch type wave clock having the antenna structure.
2. Description of the Prior Art
In a wave clock, ferrite is preferable for a material of a magnetic core of a reception antenna for receiving a standard wave in a long-wave mode, which contains time information, in consideration of loss such as eddy current loss and cost. However, ferrite is extremely brittle and easily breakable.
Therefore, in order to prevent external shock to the ferrite, it has been proposed and known that a magnetic core comprising ferrite is attached to an elastic member such as rubber at two ends, and then the elastic member is attached to a frame (JP-A-2003-110341).
However, the technology disclosed in the JP-A-2003-110341 is limitedly applied to a table clock and the like because it is limitedly used for those that can utilize an elastic member having sufficient size to absorb the shock, in addition, limitedly used for those that usually get comparatively small shock.
On the other hand, it is also proposed that a bobbin having a central, small-diameter tube part and a large-diameter tube part extending from outer circumferences of flanges at two ends of the small-diameter tube part to two end sides is fitted in a rod-like ferrite, and then a wire is wound on the small-diameter tube part to form a coil, and spring projections are provided between the large-diameter tube part and ends of the ferrite core to prevent shock to the ferrite core (JP-A-2004-125606).
In the proposed support structure, although shock to the ferrite core can be prevented by the bobbin and the spring projection, loss tends to be caused by the interposition of the bobbin, in addition, size becomes large due to the interposition of the bobbin and the spring projection.
The invention, which was made in the light of the points, aims to provide an antenna frame that can restrain the shock to the antenna and position the antenna while controlling increase in size to a minimum, and an antenna structure having the frame, and a wave clock having the antenna structure.